As audio technologies are booming, people have higher requirements on spatial attributes of sound while seeking 3D visual experience. A more realistic immersive experience effect can be generated by combining a video with an audio in a terminal device. In current application, a most common terminal device playback device is a head-mounted terminal device. Miniature microphones are placed at two earpieces of the head-mounted terminal device to collect binaural sound signals. After the collected binaural sound signals undergo processes of amplification, transmission, recording, and the like, sound is played back by using the earpieces of the head-mounted terminal device. Therefore, main spatial information consistent with that of an original sound field is generated at two ears of a listener, and playback of the spatial information of the sound is implemented. A spatial auditory effect generated by a virtual auditory playback system based on binaural sound signals is more realistic and natural.
However, when the earpieces of the head-mounted terminal device are used to play back binaural sound signals, because an earpiece playback manner is different from that of the original sound field, cognition information for determining a front/rear orientation is lost, and a problem of front/rear sound image confusion occurs. A case of sound image confusion occurs because in various factors for determining a direction of a sound source, an interaural time difference (ITD) and an interaural level difference (ILD) can determine a cone of confusion of the sound source only, but cannot determine the direction of the sound source. Due to the problem of front/rear sound image confusion, the listener may determine a front sound image as a rear sound image, or determine a rear sound image as a front sound image. In addition, a probability of incorrectly determining a front sound image as a rear sound image is far greater than a probability of incorrectly determining a rear sound image as a front sound image. Therefore, a problem urgently to be resolved is how to improve a problem of incorrectly determining a front sound image as a rear sound image during sound playback of the terminal device.